JPS61183459A - Formation of protective film - Google Patents

Abstract

PURPOSE:To obtain the very low coefft. of friction and to maintain lubricity for a long period when a protective film is formed on the surface of a member to be protected by sputtering, by using a target blank material composed or at least one kind of org. polymer and at least one kind of boron compound. CONSTITUTION:The target blank material is composed of at least one kind of the org. polymer and at least one kind of the boron compound, and the protective film is formed on the surface of the member to be protected by sputtering with the target. The org. polymer is selected from one or more kinds among phenol resin, furan resin, xylene-formaldehyde resin, urea resin, melamine resin, etc., and the boron compound is selected from one or 2>= kinds among Ta2B, Mo2B, W2B, Mn2B, CrB2, NbB, etc.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to magnetic recording media, video disks, vinyl records,
The present invention relates to a method for forming a protective film for ceramic substrates, semiconductor substrates, metal conductors, etc., and particularly relates to a method for forming a protective film with improved sliding resistance and moisture resistance.

[Background of the invention]

magnetic disks, magnetic tapes, video discs.

Information recording media such as record discs are required to have a sliding resistant lubricating oil or solid lubricating layer of 10 to 10,000 A on their surfaces to withstand sliding with the head. Methods for forming such a thin film uniformly include forming a monomolecular layer of metal soap using a pulling method, forming a polymer film on a substrate using a monomer using a plasma polymerization method, and forming a polymer film on a substrate using an organic polymer. A method of obtaining a protective film by sputtering molecules is known.

Among the above methods, the method for forming a protective film by sputtering is
For example, as taught in Japanese Patent Publication No. 57-11677, it is excellent in terms of simplicity and uniformity of the film, and is considered to be an effective film forming method for various members to be protected.

However, as a result of various experiments, it was found that organic polymer films obtained by sputtering have a high coefficient of friction and poor sliding resistance. This is particularly noticeable when the bonding property with the base is poor or when the base surface is oxidized or rough.

It has also been found that when these protective films are used as moisture-resistant protective films for metal conductors, semiconductors, ceramic substrates, etc., the moisture resistance is poor due to weak bonding with the protected member.

[Object of the Invention] An object of the present invention is to eliminate the drawbacks of the above-mentioned conventional techniques and provide a method for forming a protective film that has a low coefficient of friction, high sliding resistance, high adhesion, and excellent moisture resistance. There is a particular thing.

[Summary of the invention]

While investigating a protective film, the inventors discovered that if the target material used for sputtering is only an organic polymer, there are limits to the properties of the protective film such as sliding resistance, coefficient of friction, adhesion, etc. Furthermore, we confirmed that among various target materials, boron compounds have the above-mentioned properties, especially the property of improving the coefficient of friction. However, when using boron compounds alone, the formed film is brittle and has poor impact resistance. reached.

The present invention was made based on such knowledge, and it is based on the method for forming a protective film of an organic polymer by sputtering, in which the target material used is composed of at least one organic polymer and at least an IWi boron compound. Features. By doing so, it is possible to obtain an extremely low coefficient of friction, maintain lubricity and wetness over a long period of time, and obtain a protective film with good physical and chemical properties.

As a sputtering method for implementing the present invention,
All known methods such as direct current, low frequency, radio frequency (RF), and microwave sputtering using glow discharge, ion beam sputtering, etc. can be used. Among these, the parallel electrode type RF sputtering method and the magnetron type RF sputtering method are particularly suitable. In the case of RF sputtering, a discharge power range of 0.01 to 70 W/Fff2 can be used, and a range of 0.1 to 20 W/cWt2 is particularly desirable.

Further, the pressure of the atmospheric gas may be any pressure within the range where glow discharge occurs;
A range of rr is desirable.

Furthermore, the atmospheric gases used for sputtering in the present invention include He, No, Ar, Kr,
In addition to inert gases such as Xs, 02 # N2 y
Any one kind or a mixture of two or more kinds of reactive gases such as N2 may be used.

In addition, for mixing reactive gas with inert gas, Ar
+o2. Ar +N2, Ar +H2, Ar
+N2 +H2 is good, and a mixing ratio of 1 to 10% relative to Ar is effective. Furthermore, the effect of the reactive gas is that in the case of 02, carbonization of the organic polymer sputtered film is promoted, and in the case of N2C, c3N is added into the organic polymer sputtered film.

In the case of N2, it causes a reaction of CH2 and CH to prevent oxidation and stabilize the sputtered film.

Examples of organic polymers that can be used as targets in the present invention include the following.

That is, other thermosetting resins such as phenolic resins, furan resins, xylene formaldehyde resins, urea resins, melamine resins, aniline resins, alkyd resins, unsaturated polyester resins, epoxy resins, polyurethane resins,
and polypropylene/, poly P-xylylene, polyvinyl acetate, polyacrylate, polymethacrylate, polyvinyl chloride, polyvinylidene chloride, polyacrylonitrile, polyvinyl ether, polyvinyl ketone.

polyether, polycarbonate, polyamide.

Other thermoplastic resins such as diene plastics and thermoplastic polyurethane plastics.

Further examples include fluororesins and polyimide resins.

Among these, thermosetting resins such as phenol resins, melamine resins, unsaturated polyester resins, epoxy resins, and polyimide resins, as well as polyvinyl acetate, polyvinyl chloride, and polyvinylidene chloride.

Thermoplastic resins such as polyamide and fluororesin are suitable as target materials. In addition, these polymers may be combined. Target combinations include thermosetting resins, thermoplastic resins, and thermosetting resins and thermoplastic resins. In particular, the following combinations are possible: is good.

Phenol resin and epoxy resin, epoxy resin and polyimide resin, thermosetting resins of phenol resin and polyimide resin, polyvinyl chloride and polyvinylidene chloride,
Combinations of polyamide and polyvinylidene chloride, polyamide and fluororesin thermoplastic resins, and phenolic resins and polyvinylidene, epoxy resins and polyamides, polyamides and phenolic resins, phenolic resins and fluororesins, epoxy resins and fluororesins There are combinations of thermoplastic resins and thermosetting resins such as polyimide resin and fluororesin, polyimide resin and polyamide, polyimide resin and polyvinylidene chloride, and other combinations such as epoxy resin, polyamide, and polyimide resin. A combination of species may also be used.

In addition, boron compounds WB that can be used in the present invention,
TaB, Ta3B11. Nb5BB, Mn
3Bq, AtB2, MgB2.

TiB2, C(IBII, YJ, CaB6
, BaH2, NaBq, ZrB12.

Borides such as H3BO3, H2B, 07. )In2
Examples include boric acid such as boric acid esters, boric acid salts, and boron oxides such as boron nitride a, B2O5#, BuO5e, and B4O5.

Among these, especially AtB2, TiB2, Cr
B2, B2C)5.

Boron nitride is suitable, and combinations of 2aE or higher include AtB2 and B2O311jl boron CrB2,
TiB2 and B20, boron nitride and 8205 and T
iB2 etc. are effective.

[Embodiments of the invention]

Hereinafter, the present invention will be described in more detail based on examples. ・Figure 1 (&) M (b) I (e) shows the shape 1 of the target when using two or more types of organic polymer targets or boron compounds. It is a figure shown about a combination.

Further, a second example of the sputtering method of the present invention is also described.
Shown in the figure.

In FIG. 1, the target material to be sputtered is arranged in equal parts, and FIG. 1(a) shows a combination of organic polymer 1 and boron compound 2, and FIG. 1(b) shows a combination of first organic polymer 1.
This is an example of a combination of the boron compound 2 and the second organic polymer compound 2, the second organic polymer 3 or the boron compound 3 and the fourth organic polymer 4 or the boron compound 404. When increasing the number of target materials, the number of divisions may be increased in accordance with the above. Furthermore, even when there is a plurality of targets, each target can be composed of a plurality of target materials as described above.

In addition, in the present invention, in addition to the above-mentioned equally divided targets,
It has been confirmed that similar effects can be obtained using a target in which a boron compound is dispersed in an organic polymer.

Figures 2(b) and 2(b) are schematic diagrams of the electrode arrangement when performing composite or layered sputtering. Figure 2(a)
The target shown in FIG. 1 is attached to the target side electrode 5, the substrate 7 of the member to be protected is placed on the substrate side electrode 6, and while rotating the electrode 6, the target material is uniformly applied in a desired amount. In this example, it is formed on the surface of the substrate 70. Second
In Figure (b), a film of two or more layers is formed by attaching one or more types of targeters shown in Figure 1 to the target side electrode 5 and inverting the substrate side electrode 6 (180'). This is an example. Moreover, even if the example of FIG. 2(b) is used, the same combination as that of FIG. 2(IL) is also possible.

FIG. 3 is a schematic diagram of a sputtering apparatus used in the present invention. FIG. 4 is a partially enlarged view of the protected member 7 in FIG.
13 is a substrate made of silicon etc., 12 is r-F・203
It is a magnetic recording layer consisting of. FIG. 3 shows a target-side electrode, 8 a chamber, 9 a vacuum valve, and 10 an atmospheric gas introduction valve.

A protective film shown in FIG. 4 is formed using such a sputtering apparatus.

An example of a method for forming the protective film can be performed as follows. First, substrate 13 (81 wafer with a diameter of 3 inches)
The magnetic recording layer 12 (r -Fe205) provided above is used as an anode, and the protective film material (organic polymer and boron compound) is used as a cathode. or Ar+02°Ar+
N2, Ar+H2, Ar+N2+H2),
The gas pressure is fixed at lXl0-'Torr~0.5 Torr. Then, a glow discharge is generated using a high frequency (13,56 MHz) (discharge power 0.I W/cm2 ~ ω
W/ad), a protective film 11 is formed on the magnetic recording layer 12.

Using the sputtering method described above, a protective film was formed using various combinations of the organic polymer materials of the four rice species and a plurality of boron compounds, and the wear resistance of the protective film was evaluated.

The friction coefficient and adhesion force were measured. The table shows the experimental results.

(Left below) In order to compare the protective film formed by the present invention with the protective film formed by the conventional method, the characteristics of the conventional protective film are shown in Experimental Example &46.

〔Effect of the invention〕

As is clear from this table, the protective films formed according to the present invention (Experimental Examples 1 to 45) were 1.
It has up to 10 times higher abrasion resistance, a friction coefficient of 1/2 to 1/1 or less, and 2 to 5 times higher adhesion, making it very effective as a protective film.

[Brief explanation of the drawing]

FIG. 1 is a top view of a target used in an embodiment of the present invention, FIG. 2 is a perspective view of an electrode structure of a sputtering device used in an embodiment of the present invention, and FIG. 3 is a top view of a target used in an embodiment of the present invention. The schematic diagram and FIG. 4 are partially enlarged sectional views of a magnetic recording medium on which a protective film is formed. 1... Organic polymer material, 2... Boron compound material, 3...
...Organic polymer material or boron compound material, 4...Organic polymer material or boron compound material, 5...Target side electrode, 6...Substrate side electrode, 7...Substrate of protected member, 8
...Chamber, 9...Vacuum valve, 10...
・Atmospheric gas introduction valve, 11...Protective film, 12...
- Magnetic recording layer, 13...substrate. Agent Patent Attorney Tadashi Akimoto Figure 1 ((II) (b) (C) Figure 2 (b)

Claims (1)

[Claims] 1. A method for forming a protective film on the surface of a protected member by sputtering, characterized in that the target material is composed of at least one type of organic polymer compound and at least one type of boron compound.